Why did the Jews hate samaritans?

After the ten-tribe kingdom of Israel fell to the Assyrians in the eighth century B.C.E. The Assyrians carried many Israelites into exile, thereafter replacing them with foreign peoples.—2 Ki. 17:22-24; Ezra 4:1, 2. They turned to calf worship. Racially, the Samaritans appear to have been descendants of remaining Israelites and the foreign peoples brought into the land. In the centuries that followed, the Samaritans did not have any contact with the worship of Jehovah at Jerusalem and so continued to differ religiously from the Jews.
The racial and religious divisions existing between the Jews and Samaritans gave rise to considerable prejudice. The Jews generally looked down on the Samaritans and refused to have any dealings with them. (John 4:9) The term “Samaritan” was even used as an expression of reproach.
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